package com.atzxh.datastructure.Stack;

import java.util.Scanner;

/**
 * @author 小红同学
 * @create 2022-10-09-15:16
 * @description
 */
public class ArrayStackDemo {

    public static void main(String[] args) {

        ArrayStack stack = new ArrayStack(4);
        String key = "";
        boolean loop = true;
        Scanner scanner = new Scanner(System.in);

        while (loop){
            System.out.println();
            System.out.println("show: 显示栈");
            System.out.println("exit: 退出程序");
            System.out.println("push: 表示添加数据");
            System.out.println("pop: 表示取出一个数据");
            System.out.println("请输入你的选择");
            key = scanner.next();
            switch (key){
                case "show":
                    stack.list();
                    break;
                case "exit":
                    scanner.close();
                    loop = false;
                    break;
                case "push":
                    System.out.println("请输入一个整数");
                    int value = scanner.nextInt();
                    stack.push(value);
                    break;
                case "pop":
                    try {
                        int result = stack.pop();
                        System.out.println("出栈的数据：" + result);
                    } catch (Exception e) {
                        System.out.println(e.getMessage());
                    }
                    break;
                default:
                    break;
            }
        }
        System.out.println("程序已经退出！！！！");
    }
}

class ArrayStack{
    private int maxSize;
    private int[] stack;
    private int top = -1;

    public ArrayStack(int maxSize){
        this.maxSize = maxSize;
        stack = new int[maxSize];
    }

    //栈满
    public boolean isFull(){
        return top == maxSize -1;
    }

    //栈空
    public boolean isEmpty(){
        return top == -1;
    }

    //入栈
    public void push(int value){
        if (isFull()){
            System.out.println("栈满!!!");
            return;
        }
        top++;
        stack[top] = value;
    }

    //出栈
    public int pop(){
        if (isEmpty()){
            //抛异常
            throw new RuntimeException("栈空");
        }

        int value = stack[top];
        top--;
        return value;
    }

    //遍历
    public void list(){
        if (isEmpty()){
            System.out.println("栈空！！！");
        }

        for (int i = top; i >= 0; i--){
            System.out.printf("stack[%d] = %d\n",i,stack[i]);
        }
    }
}